I. Field of the Invention
The present invention relates generally to conveyors and, more particularly, to a conveyor with means for heating articles as they are transported by the conveyor.
II. Description of the Prior Art
The canning or bottling of potable goods, such as carbonated beverages, is typically carried out at a relatively low temperature, for example, 35 degrees F. Such a low temperature during the canning or bottling of the potable goods prevents foaming of the carbonated beverage during filling.
Following the bottling or canning process, however, excessive water condensation on the exterior of the can or bottle is a common occurrence due to the low temperature of the can or bottle. Such water condensation, moreover, is disadvantageous for a number of reasons. In the event that the article is a bottle, the water condensation will prevent labels from adhering to the bottle. In the event that the article is a can, such cans are typically placed in cardboard containers and water condensation on the exterior of the can will wet and weaken these cardboard containers.
In view of the undesirability of water condensation on the bottles or cans prior to their labeling and/or packaging, it has been the previous practice to first heat these containers following the bottling or canning operation to approximately room temperature, i.e., 72-75 degrees F. Once these containers are heated to room temperature, water condensation on the container is virtually eliminated.
It has been the previous practice to use hot water sprays to heat the containers to room temperature. Typically, the conveyors are transported along a conveyor line while a hot water sprayer above the conveyor line sprays water down onto the containers and, in doing so, heats them to room temperature. After impinging on the bottles, the water from the spray is either drained away to the available sewage system or reheated for recirculation to the sprayer.
These previously known water spray devices for the heating the containers on the conveyor line, are not efficient in operation. First, the water emitting from the sprayers must be extremely hot in order to merely heat the containers to room temperature. Moreover, the mere impingement of the hot water on the containers results in inefficient heat transfer between the water and the container and, in addition, some of the water from the sprayers misses the containers altogether and directly enters the drain. This, of course, results in no heat transfer whatsoever between the water and the containers.
A still further disadvantage of these previously known hot water sprays is that the water which enters the drain and is subsequently disposed of is still relatively hot although somewhat cooler than the water emitting from the sprayer. The disposal of this relatively hot water still further increases the energy inefficiency of these previously known systems.